This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. In this project we aim to establish novel high-resolution magnetic resonance imaging (MRI) technique, T1[unreadable], as quantitative methods sensitive to neuronal loss in the brain. We will investigate the predictive/discriminatory ability of the T1[unreadable] using a unilateral 6-hydroxydopamine (6-OHDA) PD mouse model (intrastriatal injection of 2 [unreadable]g 6-OHDA/[unreadable]L). We will study the functional relationship between T1[unreadable] with neuronal density in aphakia mice (where the deficit of dopaminergic neurons in substantia nigra and the pathways for survival of neurons are well investigated). Once validated, the technique proposed here can be used as a valuable tool to investigate if and how neuronal loss in substantia nigra is correlated with the progression of Parkinson's disease.